0803633106
As preparation for multi-target, this patch makes each inferior have
its own thread list.
This isn't absolutely necessary for multi-target, but simplifies
things. It originally stemmed from the desire to eliminate the
init_thread_list calls sprinkled around, plus it makes it more
efficient to iterate over threads of a given inferior (no need to
always iterate over threads of all inferiors).
We still need to iterate over threads of all inferiors in a number of
places, which means we'd need adjust the ALL_THREADS /
ALL_NON_EXITED_THREADS macros. However, naively tweaking those macros
to have an extra for loop, like:
#define ALL_THREADS (thr, inf) \
for (inf = inferior_list; inf; inf = inf->next) \
for (thr = inf->thread_list; thr; thr = thr->next)
causes problems with code that does "break" or "continue" within the
ALL_THREADS loop body. Plus, we need to declare the extra "inf" local
variable in order to pass it as temporary variable to ALL_THREADS
(etc.)
It gets even trickier when we consider extending the macros to filter
out threads matching a ptid_t and a target. The macros become tricker
to read/write. Been there.
An alternative (which was my next attempt), is to replace the
ALL_THREADS etc. iteration style with for_each_all_threads,
for_each_non_exited_threads, etc. functions which would take a
callback as parameter, which would usually be passed a lambda.
However, I did not find that satisfactory at all, because the
resulting code ends up a little less natural / more noisy to read,
write and debug/step-through (due to use of lambdas), and in many
places where we use "continue;" to skip to the next thread now need to
use "return;". (I ran into hard to debug bugs caused by a
continue/return confusion.)
I.e., before:
ALL_NON_EXITED_THREADS (tp)
{
if (tp->not_what_I_want)
continue;
// do something
}
would turn into:
for_each_non_exited_thread ([&] (thread_info *tp)
{
if (tp->not_what_I_want)
return;
// do something
});
Lastly, the solution I settled with was to replace the ALL_THREADS /
ALL_NON_EXITED_THREADS / ALL_INFERIORS macros with (C++20-like) ranges
and iterators, such that you can instead naturaly iterate over
threads/inferiors using range-for, like e.g,.:
// all threads, including THREAD_EXITED threads.
for (thread_info *tp : all_threads ())
{ .... }
// all non-exited threads.
for (thread_info *tp : all_non_exited_threads ())
{ .... }
// all non-exited threads of INF inferior.
for (thread_info *tp : inf->non_exited_threads ())
{ .... }
The all_non_exited_threads() function takes an optional filter ptid_t as
parameter, which is quite convenient when we need to iterate over
threads matching that filter. See e.g., how the
set_executing/set_stop_requested/finish_thread_state etc. functions in
thread.c end up being simplified.
Most of the patch thus is about adding the infrustructure for allowing
the above. Later on when we get to actual multi-target, these
functions/ranges/iterators will gain a "target_ops *" parameter so
that e.g., we can iterate over all threads of a given target that
match a given filter ptid_t.
The only entry points users needs to be aware of are the
all_threads/all_non_exited_threads etc. functions seen above. Thus,
those functions are declared in gdbthread.h/inferior.h. The actual
iterators/ranges are mainly "internals" and thus are put out of view
in the new thread-iter.h/thread-iter.c/inferior-iter.h files. That
keeps the gdbthread.h/inferior.h headers quite a bit more readable.
A common/safe-iterator.h header is added which adds a template that
can be used to build "safe" iterators, which are forward iterators
that can be used to replace the ALL_THREADS_SAFE macro and other
instances of the same idiom in future.
There's a little bit of shuffling of code between
gdbthread.h/thread.c/inferior.h in the patch. That is necessary in
order to avoid circular dependencies between the
gdbthread.h/inferior.h headers.
As for the init_thread_list calls sprinkled around, they're all
eliminated by this patch, and a new, central call is added to
inferior_appeared. Note how also related to that, there's a call to
init_wait_for_inferior in remote.c that is eliminated.
init_wait_for_inferior is currently responsible for discarding skipped
inline frames, which had to be moved elsewhere. Given that nowadays
we always have a thread even for single-threaded processes, the
natural place is to delete a frame's inline frame info when we delete
the thread. I.e., from clear_thread_inferior_resources.
gdb/ChangeLog:
2018-11-22 Pedro Alves <palves@redhat.com>
* Makefile.in (COMMON_SFILES): Add thread-iter.c.
* breakpoint.c (breakpoints_should_be_inserted_now): Replace
ALL_NON_EXITED_THREADS with all_non_exited_threads.
(print_one_breakpoint_location): Replace ALL_INFERIORS with
all_inferiors.
* bsd-kvm.c: Include inferior.h.
* btrace.c (btrace_free_objfile): Replace ALL_NON_EXITED_THREADS
with all_non_exited_threads.
* common/filtered-iterator.h: New.
* common/safe-iterator.h: New.
* corelow.c (core_target_open): Don't call init_thread_list here.
* darwin-nat.c (thread_info_from_private_thread_info): Replace
ALL_THREADS with all_threads.
* fbsd-nat.c (fbsd_nat_target::resume): Replace
ALL_NON_EXITED_THREADS with inf->non_exited_threads.
* fbsd-tdep.c (fbsd_make_corefile_notes): Replace
ALL_NON_EXITED_THREADS with inf->non_exited_threads.
* fork-child.c (postfork_hook): Don't call init_thread_list here.
* gdbarch-selftests.c (register_to_value_test): Adjust.
* gdbthread.h: Don't include "inferior.h" here.
(struct inferior): Forward declare.
(enum step_over_calls_kind): Moved here from inferior.h.
(thread_info::deletable): Definition moved to thread.c.
(find_thread_ptid (inferior *, ptid_t)): Declare.
(ALL_THREADS, ALL_THREADS_BY_INFERIOR, ALL_THREADS_SAFE): Delete.
Include "thread-iter.h".
(all_threads, all_non_exited_threads, all_threads_safe): New.
(any_thread_p): Declare.
(thread_list): Delete.
* infcmd.c (signal_command): Replace ALL_NON_EXITED_THREADS with
all_non_exited_threads.
(proceed_after_attach_callback): Delete.
(proceed_after_attach): Take an inferior pointer instead of an
integer PID. Adjust to use range-for.
(attach_post_wait): Pass down inferior pointer instead of pid.
Use range-for instead of ALL_NON_EXITED_THREADS.
(detach_command): Remove init_thread_list call.
* inferior-iter.h: New.
* inferior.c (struct delete_thread_of_inferior_arg): Delete.
(delete_thread_of_inferior): Delete.
(delete_inferior, exit_inferior_1): Use range-for with
inf->threads_safe() instead of iterate_over_threads.
(inferior_appeared): Call init_thread_list here.
(discard_all_inferiors): Use all_non_exited_inferiors.
(find_inferior_id, find_inferior_pid): Use all_inferiors.
(iterate_over_inferiors): Use all_inferiors_safe.
(have_inferiors, number_of_live_inferiors): Use
all_non_exited_inferiors.
(number_of_inferiors): Use all_inferiors and std::distance.
(print_inferior): Use all_inferiors.
* inferior.h: Include gdbthread.h.
(enum step_over_calls_kind): Moved to gdbthread.h.
(struct inferior) <thread_list>: New field.
<threads, non_exited_threads, threads_safe>: New methods.
(ALL_INFERIORS): Delete.
Include "inferior-iter.h".
(ALL_NON_EXITED_INFERIORS): Delete.
(all_inferiors_safe, all_inferiors, all_non_exited_inferiors): New
functions.
* inflow.c (child_interrupt, child_pass_ctrlc): Replace
ALL_NON_EXITED_THREADS with all_non_exited_threads.
* infrun.c (follow_exec): Use all_threads_safe.
(clear_proceed_status, proceed): Use all_non_exited_threads.
(init_wait_for_inferior): Don't clear inline frame state here.
(infrun_thread_stop_requested, for_each_just_stopped_thread): Use
all_threads instead of ALL_NON_EXITED_THREADS.
(random_pending_event_thread): Use all_non_exited_threads instead
of ALL_NON_EXITED_THREADS. Use a lambda for repeated code.
(clean_up_just_stopped_threads_fsms): Use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
(handle_no_resumed): Use all_non_exited_threads instead of
ALL_NON_EXITED_THREADS. Use all_inferiors instead of
ALL_INFERIORS.
(restart_threads, switch_back_to_stepped_thread): Use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS.
* linux-nat.c (check_zombie_leaders): Replace ALL_INFERIORS with
all_inferiors.
(kill_unfollowed_fork_children): Use inf->non_exited_threads
instead of ALL_NON_EXITED_THREADS.
* linux-tdep.c (linux_make_corefile_notes): Use
inf->non_exited_threads instead of ALL_NON_EXITED_THREADS.
* linux-thread-db.c (thread_db_target::update_thread_list):
Replace ALL_INFERIORS with all_inferiors.
(thread_db_target::thread_handle_to_thread_info): Use
inf->non_exited_threads instead of ALL_NON_EXITED_THREADS.
* mi/mi-interp.c (multiple_inferiors_p): New.
(mi_on_resume_1): Simplify using all_non_exited_threads and
multiple_inferiors_p.
* mi/mi-main.c (mi_cmd_thread_list_ids): Use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
* nto-procfs.c (nto_procfs_target::open): Don't call
init_thread_list here.
* record-btrace.c (record_btrace_target_open)
(record_btrace_target::stop_recording)
(record_btrace_target::close)
(record_btrace_target::record_is_replaying)
(record_btrace_target::resume, record_btrace_target::wait)
(record_btrace_target::record_stop_replaying): Use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS.
* record-full.c (record_full_wait_1): Use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
* regcache.c (cooked_read_test): Remove reference to global
thread_list.
* remote-sim.c (gdbsim_target::create_inferior): Don't call
init_thread_list here.
* remote.c (remote_target::update_thread_list): Use
all_threads_safe instead of ALL_NON_EXITED_THREADS.
(remote_target::process_initial_stop_replies): Replace
ALL_INFERIORS with all_non_exited_inferiors and use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS.
(remote_target::open_1): Don't call init_thread_list here.
(remote_target::append_pending_thread_resumptions)
(remote_target::remote_resume_with_hc): Use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
(remote_target::commit_resume)
(remote_target::remove_new_fork_children): Replace ALL_INFERIORS
with all_non_exited_inferiors and use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
(remote_target::kill_new_fork_children): Use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS. Remove
init_thread_list and init_wait_for_inferior calls.
(remote_target::remote_btrace_maybe_reopen)
(remote_target::thread_handle_to_thread_info): Use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS.
* target.c (target_terminal::restore_inferior)
(target_terminal_is_ours_kind): Replace ALL_INFERIORS with
all_non_exited_inferiors.
* thread-iter.c: New file.
* thread-iter.h: New file.
* thread.c: Include "inline-frame.h".
(thread_list): Delete.
(clear_thread_inferior_resources): Call clear_inline_frame_state.
(init_thread_list): Use all_threads_safe instead of
ALL_THREADS_SAFE. Adjust to per-inferior thread lists.
(new_thread): Adjust to per-inferior thread lists.
(add_thread_silent): Pass inferior to find_thread_ptid.
(thread_info::deletable): New, moved from the header.
(delete_thread_1): Adjust to per-inferior thread lists.
(find_thread_global_id): Use inf->threads().
(find_thread_ptid): Use find_inferior_ptid and pass inferior to
find_thread_ptid.
(find_thread_ptid(inferior*, ptid_t)): New overload.
(iterate_over_threads): Use all_threads_safe.
(any_thread_p): New.
(thread_count): Use all_threads and std::distance.
(live_threads_count): Use all_non_exited_threads and
std::distance.
(valid_global_thread_id): Use all_threads.
(in_thread_list): Use find_thread_ptid.
(first_thread_of_inferior): Adjust to per-inferior thread lists.
(any_thread_of_inferior, any_live_thread_of_inferior): Use
inf->non_exited_threads().
(prune_threads, delete_exited_threads): Use all_threads_safe.
(thread_change_ptid): Pass inferior pointer to find_thread_ptid.
(set_resumed, set_running): Use all_non_exited_threads.
(is_thread_state, is_stopped, is_exited, is_running)
(is_executing): Delete.
(set_executing, set_stop_requested, finish_thread_state): Use
all_non_exited_threads.
(print_thread_info_1): Use all_inferiors and all_threads.
(thread_apply_all_command): Use all_non_exited_threads.
(thread_find_command): Use all_threads.
(update_threads_executing): Use all_non_exited_threads.
* tid-parse.c (parse_thread_id): Use inf->threads.
* x86-bsd-nat.c (x86bsd_dr_set): Use inf->non_exited_threads ().
1013 lines
28 KiB
C
1013 lines
28 KiB
C
/* Low level interface to ptrace, for GDB when running under Unix.
|
||
Copyright (C) 1986-2018 Free Software Foundation, Inc.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 3 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
||
|
||
#include "defs.h"
|
||
#include "frame.h"
|
||
#include "inferior.h"
|
||
#include "command.h"
|
||
#include "serial.h"
|
||
#include "terminal.h"
|
||
#include "target.h"
|
||
#include "gdbthread.h"
|
||
#include "observable.h"
|
||
#include <signal.h>
|
||
#include <fcntl.h>
|
||
#include "gdb_select.h"
|
||
|
||
#include "inflow.h"
|
||
#include "gdbcmd.h"
|
||
#ifdef HAVE_TERMIOS_H
|
||
#include <termios.h>
|
||
#endif
|
||
#include "job-control.h"
|
||
|
||
#ifdef HAVE_SYS_IOCTL_H
|
||
#include <sys/ioctl.h>
|
||
#endif
|
||
|
||
#ifndef O_NOCTTY
|
||
#define O_NOCTTY 0
|
||
#endif
|
||
|
||
static void pass_signal (int);
|
||
|
||
static void child_terminal_ours_1 (target_terminal_state);
|
||
|
||
/* Record terminal status separately for debugger and inferior. */
|
||
|
||
static struct serial *stdin_serial;
|
||
|
||
/* Terminal related info we need to keep track of. Each inferior
|
||
holds an instance of this structure --- we save it whenever the
|
||
corresponding inferior stops, and restore it to the terminal when
|
||
the inferior is resumed in the foreground. */
|
||
struct terminal_info
|
||
{
|
||
/* The name of the tty (from the `tty' command) that we gave to the
|
||
inferior when it was started. */
|
||
char *run_terminal;
|
||
|
||
/* TTY state. We save it whenever the inferior stops, and restore
|
||
it when it resumes in the foreground. */
|
||
serial_ttystate ttystate;
|
||
|
||
#ifdef HAVE_TERMIOS_H
|
||
/* The terminal's foreground process group. Saved whenever the
|
||
inferior stops. This is the pgrp displayed by "info terminal".
|
||
Note that this may be not the inferior's actual process group,
|
||
since each inferior that we spawn has its own process group, and
|
||
only one can be in the foreground at a time. When the inferior
|
||
resumes, if we can determine the inferior's actual pgrp, then we
|
||
make that the foreground pgrp instead of what was saved here.
|
||
While it's a bit arbitrary which inferior's pgrp ends up in the
|
||
foreground when we resume several inferiors, this at least makes
|
||
'resume inf1+inf2' + 'stop all' + 'resume inf2' end up with
|
||
inf2's pgrp in the foreground instead of inf1's (which would be
|
||
problematic since it would be left stopped: Ctrl-C wouldn't work,
|
||
for example). */
|
||
pid_t process_group;
|
||
#endif
|
||
|
||
/* fcntl flags. Saved and restored just like ttystate. */
|
||
int tflags;
|
||
};
|
||
|
||
/* Our own tty state, which we restore every time we need to deal with
|
||
the terminal. This is set once, when GDB first starts, and then
|
||
whenever we enter/leave TUI mode (gdb_save_tty_state). The
|
||
settings of flags which readline saves and restores are
|
||
unimportant. */
|
||
static struct terminal_info our_terminal_info;
|
||
|
||
/* Snapshot of the initial tty state taken during initialization of
|
||
GDB, before readline/ncurses have had a chance to change it. This
|
||
is used as the initial tty state given to each new spawned
|
||
inferior. Unlike our_terminal_info, this is only ever set
|
||
once. */
|
||
static serial_ttystate initial_gdb_ttystate;
|
||
|
||
static struct terminal_info *get_inflow_inferior_data (struct inferior *);
|
||
|
||
/* RAII class used to ignore SIGTTOU in a scope. */
|
||
|
||
class scoped_ignore_sigttou
|
||
{
|
||
public:
|
||
scoped_ignore_sigttou ()
|
||
{
|
||
#ifdef SIGTTOU
|
||
if (job_control)
|
||
m_osigttou = signal (SIGTTOU, SIG_IGN);
|
||
#endif
|
||
}
|
||
|
||
~scoped_ignore_sigttou ()
|
||
{
|
||
#ifdef SIGTTOU
|
||
if (job_control)
|
||
signal (SIGTTOU, m_osigttou);
|
||
#endif
|
||
}
|
||
|
||
DISABLE_COPY_AND_ASSIGN (scoped_ignore_sigttou);
|
||
|
||
private:
|
||
#ifdef SIGTTOU
|
||
sighandler_t m_osigttou = NULL;
|
||
#endif
|
||
};
|
||
|
||
/* While the inferior is running, we want SIGINT and SIGQUIT to go to the
|
||
inferior only. If we have job control, that takes care of it. If not,
|
||
we save our handlers in these two variables and set SIGINT and SIGQUIT
|
||
to SIG_IGN. */
|
||
|
||
static sighandler_t sigint_ours;
|
||
#ifdef SIGQUIT
|
||
static sighandler_t sigquit_ours;
|
||
#endif
|
||
|
||
/* The name of the tty (from the `tty' command) that we're giving to
|
||
the inferior when starting it up. This is only (and should only
|
||
be) used as a transient global by new_tty_prefork,
|
||
create_tty_session, new_tty and new_tty_postfork, all called from
|
||
fork_inferior, while forking a new child. */
|
||
static const char *inferior_thisrun_terminal;
|
||
|
||
/* Track who owns GDB's terminal (is it GDB or some inferior?). While
|
||
target_terminal::is_ours() etc. tracks the core's intention and is
|
||
independent of the target backend, this tracks the actual state of
|
||
GDB's own tty. So for example,
|
||
|
||
(target_terminal::is_inferior () && gdb_tty_state == terminal_is_ours)
|
||
|
||
is true when the (native) inferior is not sharing a terminal with
|
||
GDB (e.g., because we attached to an inferior that is running on a
|
||
different terminal). */
|
||
static target_terminal_state gdb_tty_state = target_terminal_state::is_ours;
|
||
|
||
/* See terminal.h. */
|
||
|
||
void
|
||
set_initial_gdb_ttystate (void)
|
||
{
|
||
/* Note we can't do any of this in _initialize_inflow because at
|
||
that point stdin_serial has not been created yet. */
|
||
|
||
initial_gdb_ttystate = serial_get_tty_state (stdin_serial);
|
||
|
||
if (initial_gdb_ttystate != NULL)
|
||
{
|
||
our_terminal_info.ttystate
|
||
= serial_copy_tty_state (stdin_serial, initial_gdb_ttystate);
|
||
#ifdef F_GETFL
|
||
our_terminal_info.tflags = fcntl (0, F_GETFL, 0);
|
||
#endif
|
||
#ifdef HAVE_TERMIOS_H
|
||
our_terminal_info.process_group = tcgetpgrp (0);
|
||
#endif
|
||
}
|
||
}
|
||
|
||
/* Does GDB have a terminal (on stdin)? */
|
||
|
||
static int
|
||
gdb_has_a_terminal (void)
|
||
{
|
||
return initial_gdb_ttystate != NULL;
|
||
}
|
||
|
||
/* Macro for printing errors from ioctl operations */
|
||
|
||
#define OOPSY(what) \
|
||
if (result == -1) \
|
||
fprintf_unfiltered(gdb_stderr, "[%s failed in terminal_inferior: %s]\n", \
|
||
what, safe_strerror (errno))
|
||
|
||
/* Initialize the terminal settings we record for the inferior,
|
||
before we actually run the inferior. */
|
||
|
||
void
|
||
child_terminal_init (struct target_ops *self)
|
||
{
|
||
if (!gdb_has_a_terminal ())
|
||
return;
|
||
|
||
inferior *inf = current_inferior ();
|
||
terminal_info *tinfo = get_inflow_inferior_data (inf);
|
||
|
||
#ifdef HAVE_TERMIOS_H
|
||
/* A child we spawn should be a process group leader (PGID==PID) at
|
||
this point, though that may not be true if we're attaching to an
|
||
existing process. */
|
||
tinfo->process_group = inf->pid;
|
||
#endif
|
||
|
||
xfree (tinfo->ttystate);
|
||
tinfo->ttystate = serial_copy_tty_state (stdin_serial, initial_gdb_ttystate);
|
||
}
|
||
|
||
/* Save the terminal settings again. This is necessary for the TUI
|
||
when it switches to TUI or non-TUI mode; curses changes the terminal
|
||
and gdb must be able to restore it correctly. */
|
||
|
||
void
|
||
gdb_save_tty_state (void)
|
||
{
|
||
if (gdb_has_a_terminal ())
|
||
{
|
||
xfree (our_terminal_info.ttystate);
|
||
our_terminal_info.ttystate = serial_get_tty_state (stdin_serial);
|
||
}
|
||
}
|
||
|
||
/* Try to determine whether TTY is GDB's input terminal. Returns
|
||
TRIBOOL_UNKNOWN if we can't tell. */
|
||
|
||
static tribool
|
||
is_gdb_terminal (const char *tty)
|
||
{
|
||
struct stat gdb_tty;
|
||
struct stat other_tty;
|
||
int res;
|
||
|
||
res = stat (tty, &other_tty);
|
||
if (res == -1)
|
||
return TRIBOOL_UNKNOWN;
|
||
|
||
res = fstat (STDIN_FILENO, &gdb_tty);
|
||
if (res == -1)
|
||
return TRIBOOL_UNKNOWN;
|
||
|
||
return ((gdb_tty.st_dev == other_tty.st_dev
|
||
&& gdb_tty.st_ino == other_tty.st_ino)
|
||
? TRIBOOL_TRUE
|
||
: TRIBOOL_FALSE);
|
||
}
|
||
|
||
/* Helper for sharing_input_terminal. Try to determine whether
|
||
inferior INF is using the same TTY for input as GDB is. Returns
|
||
TRIBOOL_UNKNOWN if we can't tell. */
|
||
|
||
static tribool
|
||
sharing_input_terminal_1 (inferior *inf)
|
||
{
|
||
/* Using host-dependent code here is fine, because the
|
||
child_terminal_foo functions are meant to be used by child/native
|
||
targets. */
|
||
#if defined (__linux__) || defined (__sun__)
|
||
char buf[100];
|
||
|
||
xsnprintf (buf, sizeof (buf), "/proc/%d/fd/0", inf->pid);
|
||
return is_gdb_terminal (buf);
|
||
#else
|
||
return TRIBOOL_UNKNOWN;
|
||
#endif
|
||
}
|
||
|
||
/* Return true if the inferior is using the same TTY for input as GDB
|
||
is. If this is true, then we save/restore terminal flags/state.
|
||
|
||
This is necessary because if inf->attach_flag is set, we don't
|
||
offhand know whether we are sharing a terminal with the inferior or
|
||
not. Attaching a process without a terminal is one case where we
|
||
do not; attaching a process which we ran from the same shell as GDB
|
||
via `&' is one case where we do.
|
||
|
||
If we can't determine, we assume the TTY is being shared. This
|
||
works OK if you're only debugging one inferior. However, if you're
|
||
debugging more than one inferior, and e.g., one is spawned by GDB
|
||
with "run" (sharing terminal with GDB), and another is attached to
|
||
(and running on a different terminal, as is most common), then it
|
||
matters, because we can only restore the terminal settings of one
|
||
of the inferiors, and in that scenario, we want to restore the
|
||
settings of the "run"'ed inferior.
|
||
|
||
Note, this is not the same as determining whether GDB and the
|
||
inferior are in the same session / connected to the same
|
||
controlling tty. An inferior (fork child) may call setsid,
|
||
disconnecting itself from the ctty, while still leaving
|
||
stdin/stdout/stderr associated with the original terminal. If
|
||
we're debugging that process, we should also save/restore terminal
|
||
settings. */
|
||
|
||
static bool
|
||
sharing_input_terminal (inferior *inf)
|
||
{
|
||
terminal_info *tinfo = get_inflow_inferior_data (inf);
|
||
|
||
tribool res = sharing_input_terminal_1 (inf);
|
||
|
||
if (res == TRIBOOL_UNKNOWN)
|
||
{
|
||
/* As fallback, if we can't determine by stat'ing the inferior's
|
||
tty directly (because it's not supported on this host) and
|
||
the child was spawned, check whether run_terminal is our tty.
|
||
This isn't ideal, since this is checking the child's
|
||
controlling terminal, not the input terminal (which may have
|
||
been redirected), but is still better than nothing. A false
|
||
positive ("set inferior-tty" points to our terminal, but I/O
|
||
was redirected) is much more likely than a false negative
|
||
("set inferior-tty" points to some other terminal, and then
|
||
output was redirected to our terminal), and with a false
|
||
positive we just end up trying to save/restore terminal
|
||
settings when we didn't need to or we actually can't. */
|
||
if (tinfo->run_terminal != NULL)
|
||
res = is_gdb_terminal (tinfo->run_terminal);
|
||
|
||
/* If we still can't determine, assume yes. */
|
||
if (res == TRIBOOL_UNKNOWN)
|
||
return true;
|
||
}
|
||
|
||
return res == TRIBOOL_TRUE;
|
||
}
|
||
|
||
/* Put the inferior's terminal settings into effect. This is
|
||
preparation for starting or resuming the inferior. */
|
||
|
||
void
|
||
child_terminal_inferior (struct target_ops *self)
|
||
{
|
||
/* If we resume more than one inferior in the foreground on GDB's
|
||
terminal, then the first inferior's terminal settings "win".
|
||
Note that every child process is put in its own process group, so
|
||
the first process that ends up resumed ends up determining which
|
||
process group the kernel forwards Ctrl-C/Ctrl-Z (SIGINT/SIGTTOU)
|
||
to. */
|
||
if (gdb_tty_state == target_terminal_state::is_inferior)
|
||
return;
|
||
|
||
inferior *inf = current_inferior ();
|
||
terminal_info *tinfo = get_inflow_inferior_data (inf);
|
||
|
||
if (gdb_has_a_terminal ()
|
||
&& tinfo->ttystate != NULL
|
||
&& sharing_input_terminal (inf))
|
||
{
|
||
int result;
|
||
|
||
/* Ignore SIGTTOU since it will happen when we try to set the
|
||
terminal's state (if gdb_tty_state is currently
|
||
ours_for_output). */
|
||
scoped_ignore_sigttou ignore_sigttou;
|
||
|
||
#ifdef F_GETFL
|
||
result = fcntl (0, F_SETFL, tinfo->tflags);
|
||
OOPSY ("fcntl F_SETFL");
|
||
#endif
|
||
|
||
result = serial_set_tty_state (stdin_serial, tinfo->ttystate);
|
||
OOPSY ("setting tty state");
|
||
|
||
if (!job_control)
|
||
{
|
||
sigint_ours = signal (SIGINT, SIG_IGN);
|
||
#ifdef SIGQUIT
|
||
sigquit_ours = signal (SIGQUIT, SIG_IGN);
|
||
#endif
|
||
}
|
||
|
||
if (job_control)
|
||
{
|
||
#ifdef HAVE_TERMIOS_H
|
||
/* If we can't tell the inferior's actual process group,
|
||
then restore whatever was the foreground pgrp the last
|
||
time the inferior was running. See also comments
|
||
describing terminal_state::process_group. */
|
||
#ifdef HAVE_GETPGID
|
||
result = tcsetpgrp (0, getpgid (inf->pid));
|
||
#else
|
||
result = tcsetpgrp (0, tinfo->process_group);
|
||
#endif
|
||
if (result == -1)
|
||
{
|
||
#if 0
|
||
/* This fails if either GDB has no controlling terminal,
|
||
e.g., running under 'setsid(1)', or if the inferior
|
||
is not attached to GDB's controlling terminal. E.g.,
|
||
if it called setsid to create a new session or used
|
||
the TIOCNOTTY ioctl, or simply if we've attached to a
|
||
process running on another terminal and we couldn't
|
||
tell whether it was sharing GDB's terminal (and so
|
||
assumed yes). */
|
||
fprintf_unfiltered
|
||
(gdb_stderr,
|
||
"[tcsetpgrp failed in child_terminal_inferior: %s]\n",
|
||
safe_strerror (errno));
|
||
#endif
|
||
}
|
||
#endif
|
||
}
|
||
|
||
gdb_tty_state = target_terminal_state::is_inferior;
|
||
}
|
||
}
|
||
|
||
/* Put some of our terminal settings into effect,
|
||
enough to get proper results from our output,
|
||
but do not change into or out of RAW mode
|
||
so that no input is discarded.
|
||
|
||
After doing this, either terminal_ours or terminal_inferior
|
||
should be called to get back to a normal state of affairs.
|
||
|
||
N.B. The implementation is (currently) no different than
|
||
child_terminal_ours. See child_terminal_ours_1. */
|
||
|
||
void
|
||
child_terminal_ours_for_output (struct target_ops *self)
|
||
{
|
||
child_terminal_ours_1 (target_terminal_state::is_ours_for_output);
|
||
}
|
||
|
||
/* Put our terminal settings into effect.
|
||
First record the inferior's terminal settings
|
||
so they can be restored properly later.
|
||
|
||
N.B. Targets that want to use this with async support must build that
|
||
support on top of this (e.g., the caller still needs to add stdin to the
|
||
event loop). E.g., see linux_nat_terminal_ours. */
|
||
|
||
void
|
||
child_terminal_ours (struct target_ops *self)
|
||
{
|
||
child_terminal_ours_1 (target_terminal_state::is_ours);
|
||
}
|
||
|
||
/* Save the current terminal settings in the inferior's terminal_info
|
||
cache. */
|
||
|
||
void
|
||
child_terminal_save_inferior (struct target_ops *self)
|
||
{
|
||
/* Avoid attempting all the ioctl's when running in batch. */
|
||
if (!gdb_has_a_terminal ())
|
||
return;
|
||
|
||
inferior *inf = current_inferior ();
|
||
terminal_info *tinfo = get_inflow_inferior_data (inf);
|
||
|
||
/* No need to save/restore if the inferior is not sharing GDB's
|
||
tty. */
|
||
if (!sharing_input_terminal (inf))
|
||
return;
|
||
|
||
xfree (tinfo->ttystate);
|
||
tinfo->ttystate = serial_get_tty_state (stdin_serial);
|
||
|
||
#ifdef HAVE_TERMIOS_H
|
||
tinfo->process_group = tcgetpgrp (0);
|
||
#endif
|
||
|
||
#ifdef F_GETFL
|
||
tinfo->tflags = fcntl (0, F_GETFL, 0);
|
||
#endif
|
||
}
|
||
|
||
/* Switch terminal state to DESIRED_STATE, either is_ours, or
|
||
is_ours_for_output. */
|
||
|
||
static void
|
||
child_terminal_ours_1 (target_terminal_state desired_state)
|
||
{
|
||
gdb_assert (desired_state != target_terminal_state::is_inferior);
|
||
|
||
/* Avoid attempting all the ioctl's when running in batch. */
|
||
if (!gdb_has_a_terminal ())
|
||
return;
|
||
|
||
if (gdb_tty_state != desired_state)
|
||
{
|
||
int result ATTRIBUTE_UNUSED;
|
||
|
||
/* Ignore SIGTTOU since it will happen when we try to set the
|
||
terminal's pgrp. */
|
||
scoped_ignore_sigttou ignore_sigttou;
|
||
|
||
/* Set tty state to our_ttystate. */
|
||
serial_set_tty_state (stdin_serial, our_terminal_info.ttystate);
|
||
|
||
/* If we only want output, then leave the inferior's pgrp in the
|
||
foreground, so that Ctrl-C/Ctrl-Z reach the inferior
|
||
directly. */
|
||
if (job_control && desired_state == target_terminal_state::is_ours)
|
||
{
|
||
#ifdef HAVE_TERMIOS_H
|
||
result = tcsetpgrp (0, our_terminal_info.process_group);
|
||
#if 0
|
||
/* This fails on Ultrix with EINVAL if you run the testsuite
|
||
in the background with nohup, and then log out. GDB never
|
||
used to check for an error here, so perhaps there are other
|
||
such situations as well. */
|
||
if (result == -1)
|
||
fprintf_unfiltered (gdb_stderr,
|
||
"[tcsetpgrp failed in child_terminal_ours: %s]\n",
|
||
safe_strerror (errno));
|
||
#endif
|
||
#endif /* termios */
|
||
}
|
||
|
||
if (!job_control && desired_state == target_terminal_state::is_ours)
|
||
{
|
||
signal (SIGINT, sigint_ours);
|
||
#ifdef SIGQUIT
|
||
signal (SIGQUIT, sigquit_ours);
|
||
#endif
|
||
}
|
||
|
||
#ifdef F_GETFL
|
||
result = fcntl (0, F_SETFL, our_terminal_info.tflags);
|
||
#endif
|
||
|
||
gdb_tty_state = desired_state;
|
||
}
|
||
}
|
||
|
||
/* Interrupt the inferior. Implementation of target_interrupt for
|
||
child/native targets. */
|
||
|
||
void
|
||
child_interrupt (struct target_ops *self)
|
||
{
|
||
/* Interrupt the first inferior that has a resumed thread. */
|
||
thread_info *resumed = NULL;
|
||
for (thread_info *thr : all_non_exited_threads ())
|
||
{
|
||
if (thr->executing)
|
||
{
|
||
resumed = thr;
|
||
break;
|
||
}
|
||
if (thr->suspend.waitstatus_pending_p)
|
||
resumed = thr;
|
||
}
|
||
|
||
if (resumed != NULL)
|
||
{
|
||
/* Note that unlike pressing Ctrl-C on the controlling terminal,
|
||
here we only interrupt one process, not the whole process
|
||
group. This is because interrupting a process group (with
|
||
either Ctrl-C or with kill(3) with negative PID) sends a
|
||
SIGINT to each process in the process group, and we may not
|
||
be debugging all processes in the process group. */
|
||
#ifndef _WIN32
|
||
kill (resumed->inf->pid, SIGINT);
|
||
#endif
|
||
}
|
||
}
|
||
|
||
/* Pass a Ctrl-C to the inferior as-if a Ctrl-C was pressed while the
|
||
inferior was in the foreground. Implementation of
|
||
target_pass_ctrlc for child/native targets. */
|
||
|
||
void
|
||
child_pass_ctrlc (struct target_ops *self)
|
||
{
|
||
gdb_assert (!target_terminal::is_ours ());
|
||
|
||
#ifdef HAVE_TERMIOS_H
|
||
if (job_control)
|
||
{
|
||
pid_t term_pgrp = tcgetpgrp (0);
|
||
|
||
/* If there's any inferior sharing our terminal, pass the SIGINT
|
||
to the terminal's foreground process group. This acts just
|
||
like the user typed a ^C on the terminal while the inferior
|
||
was in the foreground. Note that using a negative process
|
||
number in kill() is a System V-ism. The proper BSD interface
|
||
is killpg(). However, all modern BSDs support the System V
|
||
interface too. */
|
||
|
||
if (term_pgrp != -1 && term_pgrp != our_terminal_info.process_group)
|
||
{
|
||
kill (-term_pgrp, SIGINT);
|
||
return;
|
||
}
|
||
}
|
||
#endif
|
||
|
||
/* Otherwise, pass the Ctrl-C to the first inferior that was resumed
|
||
in the foreground. */
|
||
for (inferior *inf : all_inferiors ())
|
||
{
|
||
if (inf->terminal_state != target_terminal_state::is_ours)
|
||
{
|
||
gdb_assert (inf->pid != 0);
|
||
|
||
#ifndef _WIN32
|
||
kill (inf->pid, SIGINT);
|
||
#endif
|
||
return;
|
||
}
|
||
}
|
||
|
||
/* If no inferior was resumed in the foreground, then how did the
|
||
!is_ours assert above pass? */
|
||
gdb_assert_not_reached ("no inferior resumed in the fg found");
|
||
}
|
||
|
||
/* Per-inferior data key. */
|
||
static const struct inferior_data *inflow_inferior_data;
|
||
|
||
static void
|
||
inflow_inferior_data_cleanup (struct inferior *inf, void *arg)
|
||
{
|
||
struct terminal_info *info = (struct terminal_info *) arg;
|
||
|
||
xfree (info->run_terminal);
|
||
xfree (info->ttystate);
|
||
xfree (info);
|
||
}
|
||
|
||
/* Get the current svr4 data. If none is found yet, add it now. This
|
||
function always returns a valid object. */
|
||
|
||
static struct terminal_info *
|
||
get_inflow_inferior_data (struct inferior *inf)
|
||
{
|
||
struct terminal_info *info;
|
||
|
||
info = (struct terminal_info *) inferior_data (inf, inflow_inferior_data);
|
||
if (info == NULL)
|
||
{
|
||
info = XCNEW (struct terminal_info);
|
||
set_inferior_data (inf, inflow_inferior_data, info);
|
||
}
|
||
|
||
return info;
|
||
}
|
||
|
||
/* This is a "inferior_exit" observer. Releases the TERMINAL_INFO member
|
||
of the inferior structure. This field is private to inflow.c, and
|
||
its type is opaque to the rest of GDB. PID is the target pid of
|
||
the inferior that is about to be removed from the inferior
|
||
list. */
|
||
|
||
static void
|
||
inflow_inferior_exit (struct inferior *inf)
|
||
{
|
||
struct terminal_info *info;
|
||
|
||
inf->terminal_state = target_terminal_state::is_ours;
|
||
|
||
info = (struct terminal_info *) inferior_data (inf, inflow_inferior_data);
|
||
if (info != NULL)
|
||
{
|
||
xfree (info->run_terminal);
|
||
xfree (info->ttystate);
|
||
xfree (info);
|
||
set_inferior_data (inf, inflow_inferior_data, NULL);
|
||
}
|
||
}
|
||
|
||
void
|
||
copy_terminal_info (struct inferior *to, struct inferior *from)
|
||
{
|
||
struct terminal_info *tinfo_to, *tinfo_from;
|
||
|
||
tinfo_to = get_inflow_inferior_data (to);
|
||
tinfo_from = get_inflow_inferior_data (from);
|
||
|
||
xfree (tinfo_to->run_terminal);
|
||
xfree (tinfo_to->ttystate);
|
||
|
||
*tinfo_to = *tinfo_from;
|
||
|
||
if (tinfo_from->run_terminal)
|
||
tinfo_to->run_terminal
|
||
= xstrdup (tinfo_from->run_terminal);
|
||
|
||
if (tinfo_from->ttystate)
|
||
tinfo_to->ttystate
|
||
= serial_copy_tty_state (stdin_serial, tinfo_from->ttystate);
|
||
|
||
to->terminal_state = from->terminal_state;
|
||
}
|
||
|
||
/* See terminal.h. */
|
||
|
||
void
|
||
swap_terminal_info (inferior *a, inferior *b)
|
||
{
|
||
terminal_info *info_a
|
||
= (terminal_info *) inferior_data (a, inflow_inferior_data);
|
||
terminal_info *info_b
|
||
= (terminal_info *) inferior_data (a, inflow_inferior_data);
|
||
|
||
set_inferior_data (a, inflow_inferior_data, info_b);
|
||
set_inferior_data (b, inflow_inferior_data, info_a);
|
||
|
||
std::swap (a->terminal_state, b->terminal_state);
|
||
}
|
||
|
||
void
|
||
info_terminal_command (const char *arg, int from_tty)
|
||
{
|
||
target_terminal::info (arg, from_tty);
|
||
}
|
||
|
||
void
|
||
child_terminal_info (struct target_ops *self, const char *args, int from_tty)
|
||
{
|
||
struct inferior *inf;
|
||
struct terminal_info *tinfo;
|
||
|
||
if (!gdb_has_a_terminal ())
|
||
{
|
||
printf_filtered (_("This GDB does not control a terminal.\n"));
|
||
return;
|
||
}
|
||
|
||
if (inferior_ptid == null_ptid)
|
||
return;
|
||
|
||
inf = current_inferior ();
|
||
tinfo = get_inflow_inferior_data (inf);
|
||
|
||
printf_filtered (_("Inferior's terminal status "
|
||
"(currently saved by GDB):\n"));
|
||
|
||
/* First the fcntl flags. */
|
||
{
|
||
int flags;
|
||
|
||
flags = tinfo->tflags;
|
||
|
||
printf_filtered ("File descriptor flags = ");
|
||
|
||
#ifndef O_ACCMODE
|
||
#define O_ACCMODE (O_RDONLY | O_WRONLY | O_RDWR)
|
||
#endif
|
||
/* (O_ACCMODE) parens are to avoid Ultrix header file bug. */
|
||
switch (flags & (O_ACCMODE))
|
||
{
|
||
case O_RDONLY:
|
||
printf_filtered ("O_RDONLY");
|
||
break;
|
||
case O_WRONLY:
|
||
printf_filtered ("O_WRONLY");
|
||
break;
|
||
case O_RDWR:
|
||
printf_filtered ("O_RDWR");
|
||
break;
|
||
}
|
||
flags &= ~(O_ACCMODE);
|
||
|
||
#ifdef O_NONBLOCK
|
||
if (flags & O_NONBLOCK)
|
||
printf_filtered (" | O_NONBLOCK");
|
||
flags &= ~O_NONBLOCK;
|
||
#endif
|
||
|
||
#if defined (O_NDELAY)
|
||
/* If O_NDELAY and O_NONBLOCK are defined to the same thing, we will
|
||
print it as O_NONBLOCK, which is good cause that is what POSIX
|
||
has, and the flag will already be cleared by the time we get here. */
|
||
if (flags & O_NDELAY)
|
||
printf_filtered (" | O_NDELAY");
|
||
flags &= ~O_NDELAY;
|
||
#endif
|
||
|
||
if (flags & O_APPEND)
|
||
printf_filtered (" | O_APPEND");
|
||
flags &= ~O_APPEND;
|
||
|
||
#if defined (O_BINARY)
|
||
if (flags & O_BINARY)
|
||
printf_filtered (" | O_BINARY");
|
||
flags &= ~O_BINARY;
|
||
#endif
|
||
|
||
if (flags)
|
||
printf_filtered (" | 0x%x", flags);
|
||
printf_filtered ("\n");
|
||
}
|
||
|
||
#ifdef HAVE_TERMIOS_H
|
||
printf_filtered ("Process group = %d\n", (int) tinfo->process_group);
|
||
#endif
|
||
|
||
serial_print_tty_state (stdin_serial, tinfo->ttystate, gdb_stdout);
|
||
}
|
||
|
||
/* NEW_TTY_PREFORK is called before forking a new child process,
|
||
so we can record the state of ttys in the child to be formed.
|
||
TTYNAME is null if we are to share the terminal with gdb;
|
||
or points to a string containing the name of the desired tty.
|
||
|
||
NEW_TTY is called in new child processes under Unix, which will
|
||
become debugger target processes. This actually switches to
|
||
the terminal specified in the NEW_TTY_PREFORK call. */
|
||
|
||
void
|
||
new_tty_prefork (const char *ttyname)
|
||
{
|
||
/* Save the name for later, for determining whether we and the child
|
||
are sharing a tty. */
|
||
inferior_thisrun_terminal = ttyname;
|
||
}
|
||
|
||
#if !defined(__GO32__) && !defined(_WIN32)
|
||
/* If RESULT, assumed to be the return value from a system call, is
|
||
negative, print the error message indicated by errno and exit.
|
||
MSG should identify the operation that failed. */
|
||
static void
|
||
check_syscall (const char *msg, int result)
|
||
{
|
||
if (result < 0)
|
||
{
|
||
print_sys_errmsg (msg, errno);
|
||
_exit (1);
|
||
}
|
||
}
|
||
#endif
|
||
|
||
void
|
||
new_tty (void)
|
||
{
|
||
if (inferior_thisrun_terminal == 0)
|
||
return;
|
||
#if !defined(__GO32__) && !defined(_WIN32)
|
||
int tty;
|
||
|
||
#ifdef TIOCNOTTY
|
||
/* Disconnect the child process from our controlling terminal. On some
|
||
systems (SVR4 for example), this may cause a SIGTTOU, so temporarily
|
||
ignore SIGTTOU. */
|
||
tty = open ("/dev/tty", O_RDWR);
|
||
if (tty > 0)
|
||
{
|
||
scoped_ignore_sigttou ignore_sigttou;
|
||
|
||
ioctl (tty, TIOCNOTTY, 0);
|
||
close (tty);
|
||
}
|
||
#endif
|
||
|
||
/* Now open the specified new terminal. */
|
||
tty = open (inferior_thisrun_terminal, O_RDWR | O_NOCTTY);
|
||
check_syscall (inferior_thisrun_terminal, tty);
|
||
|
||
/* Avoid use of dup2; doesn't exist on all systems. */
|
||
if (tty != 0)
|
||
{
|
||
close (0);
|
||
check_syscall ("dup'ing tty into fd 0", dup (tty));
|
||
}
|
||
if (tty != 1)
|
||
{
|
||
close (1);
|
||
check_syscall ("dup'ing tty into fd 1", dup (tty));
|
||
}
|
||
if (tty != 2)
|
||
{
|
||
close (2);
|
||
check_syscall ("dup'ing tty into fd 2", dup (tty));
|
||
}
|
||
|
||
#ifdef TIOCSCTTY
|
||
/* Make tty our new controlling terminal. */
|
||
if (ioctl (tty, TIOCSCTTY, 0) == -1)
|
||
/* Mention GDB in warning because it will appear in the inferior's
|
||
terminal instead of GDB's. */
|
||
warning (_("GDB: Failed to set controlling terminal: %s"),
|
||
safe_strerror (errno));
|
||
#endif
|
||
|
||
if (tty > 2)
|
||
close (tty);
|
||
#endif /* !go32 && !win32 */
|
||
}
|
||
|
||
/* NEW_TTY_POSTFORK is called after forking a new child process, and
|
||
adding it to the inferior table, to store the TTYNAME being used by
|
||
the child, or null if it sharing the terminal with gdb. */
|
||
|
||
void
|
||
new_tty_postfork (void)
|
||
{
|
||
/* Save the name for later, for determining whether we and the child
|
||
are sharing a tty. */
|
||
|
||
if (inferior_thisrun_terminal)
|
||
{
|
||
struct inferior *inf = current_inferior ();
|
||
struct terminal_info *tinfo = get_inflow_inferior_data (inf);
|
||
|
||
tinfo->run_terminal = xstrdup (inferior_thisrun_terminal);
|
||
}
|
||
|
||
inferior_thisrun_terminal = NULL;
|
||
}
|
||
|
||
|
||
/* Call set_sigint_trap when you need to pass a signal on to an attached
|
||
process when handling SIGINT. */
|
||
|
||
static void
|
||
pass_signal (int signo)
|
||
{
|
||
#ifndef _WIN32
|
||
kill (inferior_ptid.pid (), SIGINT);
|
||
#endif
|
||
}
|
||
|
||
static sighandler_t osig;
|
||
static int osig_set;
|
||
|
||
void
|
||
set_sigint_trap (void)
|
||
{
|
||
struct inferior *inf = current_inferior ();
|
||
struct terminal_info *tinfo = get_inflow_inferior_data (inf);
|
||
|
||
if (inf->attach_flag || tinfo->run_terminal)
|
||
{
|
||
osig = signal (SIGINT, pass_signal);
|
||
osig_set = 1;
|
||
}
|
||
else
|
||
osig_set = 0;
|
||
}
|
||
|
||
void
|
||
clear_sigint_trap (void)
|
||
{
|
||
if (osig_set)
|
||
{
|
||
signal (SIGINT, osig);
|
||
osig_set = 0;
|
||
}
|
||
}
|
||
|
||
|
||
/* Create a new session if the inferior will run in a different tty.
|
||
A session is UNIX's way of grouping processes that share a controlling
|
||
terminal, so a new one is needed if the inferior terminal will be
|
||
different from GDB's.
|
||
|
||
Returns the session id of the new session, 0 if no session was created
|
||
or -1 if an error occurred. */
|
||
pid_t
|
||
create_tty_session (void)
|
||
{
|
||
#ifdef HAVE_SETSID
|
||
pid_t ret;
|
||
|
||
if (!job_control || inferior_thisrun_terminal == 0)
|
||
return 0;
|
||
|
||
ret = setsid ();
|
||
if (ret == -1)
|
||
warning (_("Failed to create new terminal session: setsid: %s"),
|
||
safe_strerror (errno));
|
||
|
||
return ret;
|
||
#else
|
||
return 0;
|
||
#endif /* HAVE_SETSID */
|
||
}
|
||
|
||
/* Get all the current tty settings (including whether we have a
|
||
tty at all!). We can't do this in _initialize_inflow because
|
||
serial_fdopen() won't work until the serial_ops_list is
|
||
initialized, but we don't want to do it lazily either, so
|
||
that we can guarantee stdin_serial is opened if there is
|
||
a terminal. */
|
||
void
|
||
initialize_stdin_serial (void)
|
||
{
|
||
stdin_serial = serial_fdopen (0);
|
||
}
|
||
|
||
void
|
||
_initialize_inflow (void)
|
||
{
|
||
add_info ("terminal", info_terminal_command,
|
||
_("Print inferior's saved terminal status."));
|
||
|
||
/* OK, figure out whether we have job control. */
|
||
have_job_control ();
|
||
|
||
gdb::observers::inferior_exit.attach (inflow_inferior_exit);
|
||
|
||
inflow_inferior_data
|
||
= register_inferior_data_with_cleanup (NULL, inflow_inferior_data_cleanup);
|
||
}
|